The uniball 207 BLX Assorted Gel Pens feature a quick-drying, pigment-based ink system that enables you to write tamper-proof checks and documents.Secure your signatures and data with the uniball Retractable Gel Pen. The pigment-based ink dries quickly to form a durable bond with the paper. It makes your written text impossible to tamper with once the ink is dry. Retract the pen tip at the click of a button, when not in use, to prevent the ink from drying at the tip. The 1.0 mm smooth tip produces clear text and consistent writing. An enhanced textured grip makes the retractable pen easy to hold and write with for long hours. With an assortment of colors, namely, blue, red, purple and green, this versatile pen set is apt for use in offices and educational institutes.